Problem: Khan.scratchpad.disable(); To move up to the maestro level in her piano school, Emily needs to master at least $143$ songs. Emily has already mastered $14$ songs. If Emily can master $4$ songs per month, what is the minimum number of months it will take her to move to the maestro level?
Explanation: To solve this, let's set up an expression to show how many songs Emily will have mastered after each month. Number of songs mastered $=$ $ $ Months at school $\times$ Songs mastered per month $+$ Songs already mastered Since Emily Needs to have at least $143$ songs mastered to move to maestro level, we can set up an inequality to find the number of months needed. Number of songs mastered $\geq 143$ Months at school $\times$ Songs mastered per month $ +$ Songs already mastered $\geq 143$ We are solving for the months spent at school, so let the number of months be represented by the variable $x$ We can now plug in: $x \cdot 4 + 14 \geq 143$ $ x \cdot 4 \geq 143 - 14 $ $ x \cdot 4 \geq 129 $ $x \geq \dfrac{129}{4} \approx 32.25$ Since we only care about whole months that Emily has spent working, we round $32.25$ up to $33$ Emily must work for at least 33 months.